MORRISTOWN -- Damage to the Morristown and Morris Township Library from an underground explosion is worse than expected, and it may remain closed for many months until repairs can be made, officials said.

The stone structure’s original historic section dating back to 1917 on South Street sustained severe damage Monday around 9 a.m. after an explosion ripped through the basement and first floor. Other blasts also took place in nearby manholes under South Street. No one was hurt and the cause of the explosions remains under investigation by Jersey Central Power & Light.

Officials who got their first look today at the devastation inside said it was worse than a similar underground electrical blast in 1994 that closed the library for six weeks.

Morristown Business Administrator Michael Rogers and Fire Chief Gary Desjadon said Monday’s explosion caused the following damage: an 8-inch-thick concrete first floor slab heaved upward and cleaved; walls buckled; furniture was blown apart; interior and exterior doors were blown off hinges; windows were shattered; books and materials were mangled and strewn about and a water pipe burst.

"It’s far-more extensive than I thought. It’s a bomb-like explosion," Rogers said. "All I can say is we are incredibly fortunate nobody was killed."

Library director Susan Gulick, who has worked there since 1985 and became director four days before the 1994 explosion, said, "This is so much worse (than 1994). A big cement floor slab heaved up. Metal doors are all bent like chocolate in the sun. It just makes you sick. I don’t know why the street keeps blowing up, but it’s got to stop."

Subterranean electrical and manhole explosions have plagued Morristown over the years. After manhole blasts in December and February, the Morristown Council demanded that JCP&L discuss the issue at a meeting in March.

Monday’s explosions occurred just as library employees evacuated after seeing lights flicker and a smoking manhole. Firefighters arrived just as the blast blew doors off and shattered windows.

The town closed the library due to the damage. A notice posted on the building declares it "unsafe for human occupation."

JCP&L spokesman Ron Morano said Monday there was a "fault," meaning malfunction, of underground wires serving the library and a church next door, but later said it was too early to speculate what caused the blasts.

Then late today Morano said the utility now believes a "cable fault" did not cause the blast because such malfunctions typically may blow off a manhole cover, but would not have caused an explosion that produced as much damage as in the library. He said JCP&L has not yet been given access to the library’s interior for examination, and the utility will hire an "independent expert" to assist in its investigation.

"We’re as interested as anyone else in fully understanding what led to (Monday’s) incident and to determine what steps can be taken, if necessary, to prevent similar incidents from happening in the future," Morano said. "There still remain too many unknowns as to speculate a root cause, including a JCP&L cable fault."

"A cable fault wouldn’t cause the level of damage we’ve seen," he said. "We know our cables were damaged. We don’t know that that’s what led to the events that transpired. We’re not shifting any blame. The investigation needs to be completed."

Rogers said there has been a history of these types of underground incidents. "They’re going to have some explaining to do.’’ he said. "This is not a normal occurrence and we find it unacceptable."

Most of the "priceless" archives in the building’s damaged section may be salvageable, but the library likely will remain closed for "many months," said Rogers and Gulick. It is hoped that newer library wings not directly damaged could reopen sooner.

Robert Sciarrino/The Star-LedgerMorristown resident and attorney Herb Korn, tried to return a book to the Morristown and Morris Township Library which remains closed after an underground electrical explosion caused severe damage to the 1917 section of the structure.